Inorganic Sn-X complex ligands capped CuInS2 nanocrystals with high electron mobility

摘要

We report a facile method for the synthesis of size-controlled triangular CuInS2 (CIS) semiconductor nanocrystals (NCs) in the organic phase, and then, molecular metal chalcogenide complexes capped CIS NCs can be synthesized by exchanging original organic compounds with (NH4)(4)Sn2S6 inorganic ligands in environmentally benign solvent. The properties of CIS NCs (coated by both organic and inorganic ligands) were characterized by UV-Vis spectroscopy, fourier transform infrared, transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, X-ray photoelectron spectroscopy, and dynamic light scattering. CuInS2 NCs (before and after ligand exchange) films were spin coated on cleaned ITO glass substrates, and the charge transport properties were detected by current-voltage characteristic. We observed that the ligands on the surface of CIS NCs have been exchanged successfully, and the electrical transparency of (NH4)(4)Sn2S6-CIS NCs films was obviously increased than CIS NCs with organic capping ligands.